We have a lot of older houses in New England, which we love. However it’s important to understand that these houses were built with less stringent building codes so walls are typically made from 2 x 4s, versus today’s standard 2 x 6s. Why does that matter? It means there’s less insulation in the walls, if there’s any insulation at all because that might not have been done when the house was built. That’s why preventing ice dams at their source is so challenging.
We borrowed this diagram from an article, Ice Dams: Why They Happen & Why You Don’t Want Them. You pay a lot of money to keep your home warm and toasty in the winter (or cool in the summer). The insulation in your exterior walls and attic floor slow the loss of heat, but they can’t stop it entirely. That’s why you need ventilation working in combination with insulation, to remove the warm air from your attic space.
Some people have gotten a new roof to stop ice dams, and all we can say is we hope you needed a new roof because it can’t stop ice dams. There are a lot of factors that go into heat escaping into your attic, or reasons why the ventilation isn’t working.
Steps to Preventing Ice Dams at Their Source
Before you repair all the damage caused by your recent ice dams, you need to decide how you’re going to prevent the same problem happening again? And this is a BIG decision because the insurance company will pay for repairs once, maybe a second time but they’re going to start denying the claims (or they might not renew your policy) if you don’t find and fix the reason for the ice dams forming.
So what choices do you have for preventing ice dams, and the subsequent damage they can do to your roof and your home’s interior? With an unfinished attic, you can add insulation, adequate ventilation and seal all the gaps from the “conditioned” space below the attic that’s letting heated air escape into your attic. It’s the right solution but there are a lot of problems which make it risky:
- You can’t reach into the floor cavities below the eaves to get enough insulation in these small spaces (I know, as I’ve been there).
- You’ve got enough insulation but the soffits allowing the cold air from outside to replace the warm air inside, are blocked and with blown-in insulation, it’s hard to prevent this unless you can get baffles into all the ceilings joists.
- If you’ve got 2 x 4 exterior walls, you can have heat loss through these that can make the eaves of your roof warmer underneath than the air above, where the ice dams form.
- If your attic space is finished, are you willing to open up the walls and ceilings to add insulation and/or make sure there are air channels for the necessary ventilation?
- If you’re close to needing a new roof, that’s an opportunity to add insulation on top of the roof deck. The challenge though will be finding the right contractor to do this because it’s not something a roofing company does.
Preventing Ice Dams on Top of Your Roof
So what options do you have for preventing ice dams, if you’re not able to keep your roof cold? There are several choices for warming up the top of your roof to prevent ice dams from forming, or so homeowners hope … as they don’t all work.
- Heat cables – are the first solution many homeowners think of. You can install them but they typically don’t have enough power to prevent icicles and ice dams from forming (photo).
- Metal aprons – are common on the eaves of roofs in the mountains. They work best with really steep roofs (12 pitch or higher), which is why you also see ice guards on these roofs to break the snow up when it slides off the roof.
- Metal roofs – might seem to be a logical choice for roofs prone to snow and ice problems but we’ve installed quite a few of our ice prevention systems on metal roofs like this one in Woodstock, VT (that’s me on the ladder).
- Ice prevention systems – take the heat cable concept to a much higher level. Using more powerful cables, the heat is transferred to sheets of metal that keep the eaves (and valleys) of your house warm enough so ice dams never form.
Combining Repairs & Solutions for Preventing Ice Dams
If you followed the steps outlined in the first article, Assessing the Damage from Ice Dams, you’ve done your homework – congratulations. You will hopefully get enough money from your insurance company to cover repairs and you should stay involved to make sure everything on your list gets completed. But your insurance company will be focused on repairs, not preventing ice dams.
We can’t recommend strongly enough that this is the perfect time to also install an ice prevention system for several reasons.
- You know the stress of living and dealing with snow and ice. Of trying to find someone to remove the snow from your roof, and then still finding you’ve got a roof leak with related damage … and you don’t want to relive this.
- Your lifestyle will be affected because you need to stay home to manage these problems, or hire someone to act in your absence.
- Insurance companies will cover these repairs once, and maybe a second time, they won’t keep paying. They’ll simply refuse to renew your insurance policy.
So we invite you to explore our website which explains our ice prevention system, one that works automatically once you turn the system on in the fall. You won’t have to worry again so isn’t it time to get started? Just give us a call at 877-705-1356 or submit a contact form and we’ll call you!
Photo credits: Metal apron from TraditionalRoofing.com (and there’s another photo on this page, showing wood rot due to water)